X-ray mammography and/or breast tomosynthesis using a compression paddle

ABSTRACT

An x-ray breast imaging system comprising a compression paddle in which the compression paddle comprises a front wall and a bottom wall. The front wall is configured to be adjacent and face a chest wall of a patient during imaging and the bottom wall configured to be adjacent a length of a top of a compressed breast. The bottom wall extends away from the patient&#39;s chest wall, wherein the bottom wall comprises a first portion and a second portion such that the second portion is between the front wall and the first portion. The first portion is generally non-coplanar to the second portion, wherein the compression paddle is movable along a craniocaudal axis. The x-ray breast imaging system also comprises a non-rigid jacket releasably secured to the compression paddle, the non-rigid jacket positioned between the compression paddle and the patient.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/787,076, filed Oct. 26, 2015, which is a 35 U.S.C. § 371 nationalstage entry of PCT International Patent Application No.PCT/US2014/035334, filed Apr. 24, 2014, which claims priority to and thebenefit of U.S. Provisional Patent Application No. 61/950,938, filedMar. 11, 2014; and U.S. Provisional Patent Application No. 61/816,202,filed Apr. 26, 2013. U.S. patent application Ser. No. 14/787,076 alsoclaims the benefit under 35 U.S.C. § 120 and is a continuation-in-partof U.S. patent application Ser. No. 13/679,446, filed Nov. 16, 2012, nowU.S. Pat. No. 9,332,947, which claims the benefit under 35 U.S.C. § 119to U.S. Provisional Patent Application No. 61/561,620, filed Nov. 18,2011. The disclosures of each of the foregoing applications areincorporated by reference herein in their entireties.

INTRODUCTION

A significant patient concern in x-ray mammography and breasttomosynthesis is the discomfort the patient may feel when the breast iscompressed, typically, between two rigid plastic surfaces, withsufficient force to immobilize the breast and spread out the breasttissues for x-ray imaging. One challenge is to ensure that the imagedfield includes the desired amount of breast tissue. The reasons forusing compression include: (1) to make the breast thinner in thedirection of x-ray flux and thereby reduce patient radiation exposurefrom the level required to image the thicker parts of a breast that isnot compressed; (2) to make the breast more uniform in thickness in thedirection of x-ray flux and thereby facilitate more uniform exposure atthe image plane over the entire breast image; (3) to immobilize thebreast during the x-ray exposure and thereby reduce image blurring; and(4) to bring breast tissues out from the chest wall into the imagingexposure field and thus image more tissue. As the breast is beingcompressed, typically a technician manipulates the breast to position itappropriately and counter the tendency that compression has of pushingbreast tissue toward the chest wall and out of the image field.

Standard compression methods for mammography and tomosynthesis use amovable, rigid clear plastic compression paddle in which the surfaces ofthe paddle are perpendicular to one another. The breast is placed on abreast platform that typically is flat, and the paddle is thencompressed onto the breast, usually while a technician or other healthprofessional is holding the breast in place and perhaps manipulates thebreast to ensure proper tissue coverage in the image receptor's field ofview and to help spread the breast.

One reason for discomfort that the patient may feel is that thecompression force is non-uniformly distributed throughout the breast. Itis concentrated at the thickest portion of the breast, usually near thechest wall, at or near the lower front edge of the compression paddleand the upper front corner of the breast platform. The anterior portionof the breast, such as near the nipple, may receive less compressiveforce, or no compression force. The paddle may not even contact thisportion of the breast. The terms front, lower and upper pertain to usinga CC imaging orientation, with the patient facing the front of theimaging system, although it should be understood that other imagingorientations, including MLO, are used with the same equipment and theseterms need to be adjusted accordingly.

Some systems improve patient comfort by providing compression paddlesthat tilt as the breast is being compressed. A tilting paddlearrangement is available in various paddle sizes from Lorad of Danbury,Conn., a division of the assignee hereof, Hologic, Inc. of Bedford,Mass., under the trade name F.A.S.T. (of FAST). This tilting paddleprovides more uniform compression across the breast, and morecomfortable breast examinations.

Nonlimiting examples of various approaches to compression paddles andsystems therefor include U.S. Pat. Nos. 3,971,950; 5,474,072; 5,506,877and 6,974,255, U.S. Patent Application Publication Nos. 2005/0008117,2006/0050844, and 2013/0051520, and Japanese Patent ApplicationPublication Nos. 2011-206438 and 2011-206439. Other methods forimproving patient comfort have been proposed and some have been inclinical use to improve patient comfort. One is the use of relativelythin foam pads that are placed above and/or below the breast. The paddeforms to some extent during the compression procedure and may provideimproved comfort by spreading out the pressure to a greater extent thanusing a hard-surfaced paddle and/or breast platform alone. One such padsystem is discussed in commonly owned U.S. Pat. Nos. 6,968,033,6,765,984, 6,577,702, and 7,505,555, and published U.S. PatentApplication Publication No. 2003/0007597. Another pad system is proposedin U.S. Pat. Nos. 6,850,590 and 6,975,701 and published U.S. PatentApplication Publication Nos. 2006/0050844, US 2004/0156472 and2003/0099325. Such pads are not transparent to visible light. As aresult, if such a pad is between the breast and the compression paddle,the breast will not be visible through the paddle, and this can impairthe technician's effort to position and manipulate the breast duringcompression. The pad needs to be made of fairly dense thin form, so asto provide meaningful deformability when compressed under or above thebreast. If the foam pad slips during positioning and as a result doesnot cover the entire imaging field, an edge of the pad may cause imageartifacts.

Another system for improving patient comfort has been proposed for adifferent purpose—to immobilize the breast during biopsy—by ScientificBiopsy (www.sbiopsy.com). It is understood to use a soft, trough-shapedsupport to cradle the breast and a flexible band that wraps over thebreast to impose a holding force. A thin plastic sheet compressing abreast for ultrasound examination rather than for x-ray imaging isproposed in published patent application US 2003/0007598 (see, e.g.,FIG. 7 and paragraph [0115]) but no teaching could be found that thematerial is transparent to visible light or that the arrangement isuseful for x-ray imaging or with a flat breast platform. U.S. Pat. No.6,682,484 discusses the use of a polymeric membrane stretched undertension to restrain the breast during sonographic and/or x-ray imaging.U.S. Pat. No. 7,822,457 discusses the use of tensioned membrane tocompress the breast for medical imaging, and that the membrane may betensioned with a mechanical device or by means of an inflatable bladder.U.S. Pat. No. 6,587,578 discusses a non-rigid object holder having aresilient membrane attached to a first member to form an inflatablecomponent for holding the object to be examined between the inflatablecomponent and a base support.

Commonly assigned U.S. Pat. Nos. 7,489,761 and 7,792,244 describe (1)placing a fluid-filled pillow or bag between the compression paddle andthe breast before the breast is compressed, (2) compressing the breastwith a sheet of a material such as Mylar stretched or at least supportedbetween two rods or rollers (instead of using a conventional compressionpaddle), and (3) using a paddle provided with a lining of concavecompressible material.

SUMMARY

It is believed that a need still remains to further improve breastimaging and patient comfort. The present technology is directed to newapproaches to address challenges in breast imaging and particularlyx-ray breast imaging.

One non-limiting example of such new approaches in mammography and/orbreast tomosynthesis involves the use of a specially adapted device tocontrol, distribute and re-direct breast compression forces. Preferably,the device includes a non-rigid jacket for the compression paddle.

In one aspect, the technology relates to: an x-ray breast imaging systemhaving: a compression paddle having: a front wall configured to beadjacent and face a chest wall of a patient during imaging; a bottomwall configured to extend away from the patient's chest wall and to beadjacent a length of a top of a compressed breast, wherein the bottomwall has a central portion and two outer edge portions, wherein thecentral portion is a non-coplanar with the two outer edge portions, andwherein the compression paddle is movable; and a first axissubstantially orthogonal to the front wall. In an embodiment, the twoouter edge portions define a reference plane, and wherein the centralportion is disposed above the reference plane so as to define a concavesurface extending from a first outer edge portion to the central portionto a second outer edge portion. In another embodiment, the compressionpaddle further has a rear wall disposed opposite the front wall, whereinthe central portion of the bottom wall has a pitched surface, wherein afirst distance between the central portion and the reference planeproximate the front wall is greater than a second distance betweencentral portion and the reference plane proximate the rear wall. In yetanother embodiment, the central portion of the bottom wall is pitchedalong the first axis from a high point proximate the front wall. Instill another embodiment, the system includes a breast platform, whereinthe compression paddle is adapted to be disposed in: a compressingposition wherein the compressed breast is disposed between thecompression paddle and the breast platform; and a non-compressingposition wherein the compressed breast is not disposed between thecompression paddle and the breast platform, and wherein the bottom wallhas a substantially similar contour in both the compressing position andnon-compressing position.

In another embodiment of the above aspect, a distance between thecentral portion and the reference plane is substantially identical inboth the compressing position and the non-compressing position. Inanother embodiment, movement of the compression paddle is selected froma group consisting of movable only along a craniocaudal axis, movableonly laterally, and combinations thereof. In yet another embodiment, thesystem includes an x-ray source selectively emitting an imaging x-raybeam, wherein the x-ray source is configured to move along an arc. Instill another embodiment, the x-ray breast imaging system is a breasttomosynthesis x-ray breast imaging system.

In another aspect, the technology relates to: an x-ray breast imagingsystem having: a compression paddle having a front wall, a bottom wall,and an intermediate portion between the front wall and the bottom wall,the front wall configured to be adjacent and face a chest wall of apatient during imaging and the bottom wall configured to be adjacent alength of a top of a compressed breast, the bottom wall extending awayfrom the patient's chest wall, wherein the intermediate portion isgenerally non-coplanar to the front wall and the bottom wall, whereinthe compression paddle is movable along a craniocaudal axis; and anon-rigid jacket releasably secured to the compression paddle, thenon-rigid jacket positioned between the compression paddle and thepatient. In an embodiment, the non-rigid jacket is a gel pad jacket. Inanother embodiment, the intermediate portion has a radius a generallysmooth curvature. In another embodiment a height of the intermediateportion is no taller than a height of the bottom wall. In yet anotherembodiment, a height of the intermediate portion is taller than a heightof the bottom wall such that the intermediate portion is closer to thecompressed breast relative to the bottom wall. In still anotherembodiment, the bottom wall has a concave portion and a convex portionrelative to the compressed breast.

In another embodiment of the above aspect, the convex portion is wherethe bottom wall meets the intermediate portion. In another embodiment,the intermediate portion has a curvature having a radius. In yet anotherembodiment, the front wall is slightly off-angle from vertical. In stillanother embodiment, movement of the compression paddle is selected froma group consisting of movable only along a craniocaudal axis, movableonly laterally, and combinations thereof. In another embodiment, thesystem includes an x-ray source selectively emitting an imaging x-raybeam, wherein the x-ray source is configured to move along an arc. Inanother embodiment, the x-ray breast imaging system is a breasttomosynthesis x-ray breast imaging system.

In another aspect, the technology relates to a method of imaging abreast of a patient with x-rays from an x-ray breast imaging including:supporting a bottom of the breast on a breast platform; and compressingthe breast by applying a compression paddle system to a top of thebreast, the compression paddle system having a paddle having a frontwall and a bottom wall and a non-rigid jacket coupled to the paddle, thefront wall configured to be adjacent and face a chest wall of a patientduring imaging and the bottom wall configured to be adjacent a length ofa top of a compressed breast, the bottom wall extending away from thepatient's chest wall, wherein the bottom wall has a first portion and asecond portion such that the second portion is between the front walland the first portion, the first portion generally non-coplanar to thesecond portion, the compression paddle is movable only along acraniocaudal axis, and the non-rigid jacket positioned between thecompression paddle and the breast. In an embodiment, the non-rigidjacket is an inflatable jacket. In another embodiment, the methodincludes positioning a portion of the compressed breast, the portiondistal relative to the patient's chest wall, after compressing thebreast. In another embodiment, the method includes inflating theinflatable jacket after compressing the breast. In yet anotherembodiment, the inflatable jacket is inflated with a fluid. In stillanother embodiment, the method includes moving an x-ray source over anarc and exposing the compressed breast to a plurality of x-ray beamsduring movement of the arc.

In another embodiment of the above aspect, a height of the secondportion is taller than a height of the first portion such that thesecond portion is closer to the compressed breast relative to the firsportion. In another embodiment, the bottom wall has a concave portionand a convex portion relative to the compressed breast. In anotherembodiment, the convex portion is where the first portion meets thesecond portion. In yet another embodiment, the second portion has acurvature having a radius. In still another embodiment, the front wallis slightly off-angle from vertical. In another embodiment, movement ofthe compression paddle to compress the breast is selected from a groupconsisting of movable only along a craniocaudal axis, movable onlylaterally, and combinations thereof

Still other aspects, embodiments, features and advantages of theseexemplary aspects and embodiments, are discussed in detail below. Anyfeature, advantage, implementation, embodiment, or example may becombined or form a part of any aspect or any embodiments in any mannerconsistent with at least one of the principles disclosed herein, andreferences to “an embodiment,” “some embodiments,” “an alternateembodiment,” “various embodiments,” “one embodiment,” “example,”“feature,” “advantage,” “implementation” or the like are not necessarilymutually exclusive and are intended to indicate that a particularfeature, embodiment, structure, or characteristic described may beincluded in at least one aspect. The appearances of such terms hereinare not necessarily all referring to the same embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of at least one embodiment are discussed below withreference to the accompanying figures, which are not intended to bedrawn to scale.

The figures are included to provide illustration and a furtherunderstanding of the various aspects and embodiments, and areincorporated in and constitute a part of this specification, but are notintended as a definition of the limits of the technology. In thefigures, each identical or nearly identical component that isillustrated in various figures is represented by a like numeral. Forpurposes of clarity, not every component may be labeled in every figure.In the figures:

FIG. 1 is a partly schematic view and partly a block diagram of amammography and/or tomosynthesis system using an inflatable or inflatedpaddle jacket in imaging a patient's breast with x-rays.

FIG. 2 is a partial perspective view, not to scale, which illustrates acompression paddle provided with an inflatable or inflated jacket and abreast platform with a compressible mat thereon, as a part of an x-raymammography and/or tomosynthesis system.

FIG. 3 illustrates schematically a section of the compression paddlewith a paddle jacket secured thereto.

FIG. 4 illustrates schematically two examples of ways to releasablysecure a paddle jacket to a compression paddle.

FIG. 5 illustrates schematically a seam in the paddle jacket.

FIG. 6 illustrates a variant in which the bottom of the jacket hasmultiple chambers that can be pressurized to different degrees.

FIG. 7 is a perspective view of an inflatable jacket secured to acompression paddle (upside down).

FIG. 8 illustrates a compression paddle with an inflatable jacketsecured thereto, and with the combination secured to a breast imagingsystem.

FIG. 9 illustrates a breast imaging system using an inflatable jacketover the compression paddle.

FIGS. 10A-10E illustrate schematic perspective, side, partialcross-section, top, and bottom view, respectively, of a compressionpaddle according to an embodiment of the present technology.

FIGS. 11A-11E illustrate schematic perspective, side, partialcross-section, top, and bottom view, respectively, of a compressionpaddle in accordance with an embodiment of the present technology.

FIGS. 12A-12E illustrate schematic perspective, side, partialcross-section, top, and bottom view, respectively, of a compressionpaddle according to an embodiment of the present technology.

FIGS. 13A-13B illustrate schematic side views a method of breastcompression in accordance with an embodiment of the present technology.

FIGS. 14A-14C illustrate schematic perspective and bottom views of acompression paddle according to an embodiment of the present technology.

FIGS. 15A-15C illustrate schematic perspective, front, and side views ofa compression paddle in accordance with an embodiment of the presenttechnology.

DETAILED DESCRIPTION

Except as otherwise noted, the articles “a,” “an,” and “the” mean “oneor more.”

Referring to FIG. 1, a patient's breast 10 is immobilized for x-rayimaging between a breast platform 12 and a compression paddle 16.Platform 12 can be the upper surface of a housing 14. At least anunderside of compression paddle 16 is covered with a non-rigid paddlejacket, such as, preferably, an inflatable paddle jacket 18. Platform 12and paddle 16 form a breast immobilizer unit 20 that is in a path of animaging beam 22 emanating from x-ray source 24. Beam 22 impinges onimage receptor 26 that is in housing 14.

Immobilizer 20 and housing 14 are supported on an arm 28. X-ray source24 is supported on an arm 30. For mammography, support arms 28 and 30can rotate as a unit about an axis such as at 30 a between differentimaging orientations such as CC and MLO, so that the system can take amammogram projection image Mp at each orientation. Image receptor 26remains in place relative to housing 14 while an image Mp is taken.Immobilizer 20 releases breast 10 for movement of arms 28 and 30 to adifferent imaging orientation. For tomosynthesis, support arm 28 staysin place, with breast 10 immobilized and remaining in place, while atleast source support arm 30 rotates source 24 relative to immobilizer 20and breast 10 about an axis such as 30 a.

The system takes plural tomosynthesis projection images of breast 10 atrespective angles of beam 22 relative to breast 10. Concurrently, imagereceptor 26 may be tilted relative to breast platform 12 in sync withthe rotation of source support arm 30. The tilting can be through thesame angle as the rotation of course 24, but preferably is through adifferent angle, selected such that beam 22 remains substantially in thesame position on image receptor 26 for each of the plural images Tp. Thetilting can be about an axis 32 a, which can but need not be in theimage plane of image receptor 26.

A tilting mechanism 34, which also is in housing 14 or is otherwisecoupled with receptor 24, can drive image receptor 24 in a tiltingmotion. Axes 20 a, 24 a and 26 a extend left-right as seen in FIG. 1,and may but preferably do not coincide. For tomosynthesis imaging,breast platform 12 can be horizontal or can be at an angle to thehorizontal, e.g., at an orientation similar to that for conventional MLOimaging in mammography. The system of FIG. 1 can be solely a mammographysystem, or solely a tomosynthesis system, or a “combo” system that canperform both mammography and tomosynthesis imaging. An example of such acombo system is been offered by the assignee hereof under the trade nameSelenia Dimensions. Nonlimiting examples of such a combo system or atomosynthesis system are described at U.S. Pat. Nos. 7,869,563;7,831,296; 7,583,786; 7,430,272; 7,245,694; and 7,123,684. When thesystem is operated, image receptor 26 produces imaging information inresponse to illumination by imaging beam 22, and supplies it to imageprocessor 34 for processing to generate breast x-ray images. A fluidcontrol unit 36 connects with inflatable jacket 18 via conduit 36 a,preferably through a quick-release snap-on connection 48. A systemcontrol and work station unit 38 controls the operation of the systemand interacts with a user to receive commands and deliver informationincluding processed-ray images.

Referring to FIGS. 1-6 (which are not to scale) for a more detailedillustration of breast immobilizer 20, compression paddle 16 typicallyis made of clear plastic and has a front wall 16 a, a left side wall 16b, a right side wall 16 c, and a bottom wall 16 d having an underside 16e. Side walls 16 b and 16 c are supported by a bracket 16 f that in turnis supported by support arm 28 for up-down movement along arm 28. Fortilting relative to breast 10, paddle 16 is secured to bracket 16 withpins 16 g (only the right pin is visible in FIG. 2) and is spring biasedsuch that as paddle 16 presses against breast 10 the front end of paddle16 lifts against the biasing force. If desirable, a compressible pad 40may be placed on platform 12 to increase patient comfort, as in knownfor system offered by the common assignee. In addition, compressionpaddle 16 can move left-right as in the current system offered by theassignee under the trade name Selenia Dimensions.

An inflatable jacket 18 is releasably secured to compression paddle 16and has a front wall 18 a, a left side wall 18 b, a right side wall 18c, and a bottom 18 d having a top wall 18 e facing the underside 16 e ofplatform 16 and a bottom wall 18 f. Bottom 18 d thus includes aninflatable chamber formed between walls 18 e and 18 f of jacket 18. Thischamber 18 d is in fluid flow communication with fluid control unit 36via conduit 36 a so it can be selectively inflated and, if desired,selectively deflated, to a desired pressure. A quick connect-release,snap-on connector 48 facilitates convenient connection of chamber 18 dto fluid control unit 36 and disconnection from unit 36. If desired thebottom of jacket 18 can be divided into two or more chambers, such aschambers 18 h and 18 i, by a partition 18 g, and separate conduits andconnect/disconnect device (not shown) can be provided for each so thatthe two or more chambers can be inflated to desired pressures that maydiffer from each other.

Jacket 18 can be releasably secured to paddle 16 in any number of wayssuch that it can be easily attached and removed from paddle 16 and sothat it will not undergo undesirable shifts relative to paddle 16 or thepatient's skin while the breast is being immobilized and imaged.

FIG. 3 illustrates one example, in which at least some of the surfacesof jacket 18 that face platform 16 are made of or coated with a materialthat adheres to platform 16 with a force that is sufficiently high tosubstantially prevent undesirable movement between platform 16 andjacket 18 but also sufficiently low to allow for easy removal of jacket18 from paddle 16. Preferably at least the upper wall 18 e of jacket 18is made sticky for that purpose, but any one or more of the other wallscan also be made sticky instead of or in addition to wall 16 e. In thisexample of using adhesion to releasably secure jacket 18 to paddle 16,the front and side walls of jacket 18 preferably are shorter than thecorresponding walls of paddle 16 but in the alternative can be the sameheight or even taller. The walls of jacket 18 can but need not be thesame height; for example front wall 18 a can have a lesser heightcompared with side walls 18 b and 18 c.

FIG. 4 illustrates other examples of releasably securing jacket 18 topaddle 16. In this example, at least one but preferably two or all threeof front wall 18 a and side walls 18 b and 18 c are provided withclipping members 42 that clip over the top of the respective wall ofplatform 16 and thus keep jacket 18 and platform 16 secured to eachother. Clipping member 42 can be as shown in solid lines, or it can havean extension 42 a as shown in dashed line. Jacket 18 typically is madeof a plastic material such as vinyl that is somewhat stretchable and isdimensioned for a tight fit over platform 16 such that mechanicalfriction and perhaps some electrostatic force and inherent stickiness ofthe jacket material combine to maintain the jacket and platform fromundesirable movement with respect to each other, but jacket 18 can stillbe easily peeled from paddle 16 by an operator so that a new jacket canbe installed for the next patient if desired. Other examples arecontemplated, such as snap connections between the side walls of thejacket and the compression paddle, or other mechanical connections.

Jacket 18 can be made of two layers of a material such a vinyl similarin chemical composition and thickness to that used for colostomy bagsand even kitchen food bags and freezer bags. Preferably the two layersare fused or adhered to each other at the front and side walls of jacket18, but not at the bottom 18 d of jacket 18. Preferably, a seam 44 isformed, e.g., with adhesive material or by fusing, joining the twolayers where jacket 18 adjoins the junction of the front and undersideof platform 16 when jacket 18 is secured to platform 16, as illustratedin FIG. 5. Seam 42 can extend partly over front wall 16 a and partlyover underside 16 e of platform 16, as illustrated (not to scale) inFIG. 5. Preferably, seam 42 is positioned such that the inflatablevolume 18 d of jacket 18 does not extent forward beyond front wall 16 aof platform 16, so as not to push patient tissue away from platform 16.

Referring to FIG. 6, the jacket's chamber 18 d can have two or moresub-chambers, such as shown at 18 h and 18 i, each with a respectiveconnection through a snap-on connector and a conduit to fluid controlunit 36, so that each subchamber can be inflated to a desired pressurelevel under operator control or automated system control.

Fluid control unit 36 can be powered by an operator, using a hand-pumpor a foot pump and appropriate manual or foot-controlled valves.Alternatively, electric or fluid-powered pumps can be used, withappropriate valves and interfaces such as buttons or switches that theoperator controls. As another alternative, fluid control unit 36 can befully automated such that inflation/deflation of jacket 18 is undercontrol of station 38, when so enabled by an operator, and in responseto events such as compression paddle 16 reaching a certain positionrelative to the patient's breast or to platform 12 or exerting aspecified pressure on the patient's breast. The controls overinflation/deflation can be a part of or at least associated with unit38. In use, the mammography and/or tomosynthesis system is operated asknown, for example as known for the systems offered by the commonassignee under the commercial designations Selenia and SeleniaDimensions, except for the addition of inflatable paddle jacket 18.Thus, before patient imaging, a jacket 18 is secured to paddle 16 andconnected to conduit 36 through a snap-on connector 48. With patient'sbreast 10 on platform 12 or pad 40, the technician lowers paddle 16(with jacket 18 secured thereto) to begin compressing breast 10, whilemanually manipulating the breast to spread out breast tissue and pulltissue away from the patient's chest wall and into the x-ray field ofview. In this process, the technician may control the degree ofinflation of the jacket's chamber 18 d before and/or after paddle 16 hasbeen lowered to its final desired position by adding to and/or releasingfluid from chamber 18 d. If chamber 18 d has two or more sub-chambers,the technician may individually control the inflation of each in asimilar manner. Once the technician or other health professional issatisfied with the position of breast 10, x-ray imaging can commence ina mammography and/or tomosynthesis mode, for example as known for saidsystems offered by the common assignee.

FIGS. 7-9 illustrate examples of an inflatable or inflated jacket 18secured to a compression paddle in a breast imaging system. In FIG. 7,jacket 18 and paddle 16 are upside-down to better illustrate them andquick-release coupling 48. FIG. 8 illustrates paddle 16 and jacket 18 ina more typical orientation, and also illustrates a knob 80 that can bemanually turned to move paddle 16 and its support left-right. FIG. 9illustrates in perspective view a system in which components areidentified by reference numeral used in FIG. 1 and described inconnection with FIG. 1.

While specific examples have been described above, it should be clearthat variations thereof are within the scope of the technology definedby the appended claim. As one of many possible examples, a similarinflatable jacket can be used on or over breast platform 12 in additionto or instead of using jacket 18 on compression paddle 16. In thatexample, such a jacket can be similarly secured to housing 14, or it canomit the side walls so that only a chamber similar to chamber 18 d (ormultiple sub-chambers) is present on breast platform 12, possibly with afront wall similar to front wall 18 a but extending down along the frontwall of housing 14.

Referring now to FIGS. 10A-10E, an embodiment of a compression paddle100 is shown. The compression paddle 100 can be used with any of thefeatures described herein, such as a non-rigid paddle jacket (e.g., aninflatable paddle jacket) for use with the x-ray imaging systemdescribed above, such as a breast tomosynthesis x-ray imaging system.The compression paddle 100 includes at least one projection 101extending from a surface of the compression paddle 100.

Although four projections 101 are shown, fewer or more can be utilized.The projections 101 mate with corresponding structures, such as channelsor apertures, of a non-rigid jacket. In an embodiment, the non-rigidjacket can be an inflatable jacket, thus, having resilient propertieswhen inflated or a gel pad having elastic properties. Additionally oralternatively, a distal end of the projection can be enlarged and havewidth larger than a proximal stem portion of the projection. Thecompression paddle 100 also has a front wall 102 and a bottom wall 104.The front wall 102 is configured to be adjacent and face a chest wall ofa patient. The bottom wall 104 extends away from the patient's chestwall and faces a length of a compressed breast. The bottom wall includesa first portion 106 and a second portion 108. The first portion 106 isgenerally non-coplanar to the second portion 108. In an embodiment, thesecond portion 108 is rotated about 5 degrees to about 20 degrees fromthe first portion, preferably about 10 degrees to about 15 degrees, andeven more preferably about 25 degrees. The generally non-coplanarconfiguration (e.g., a wedge-shaped configuration) between the firstportion 106 and the second portion 108 aids in locking breast tissue atthe chest wall and/or creating a vector of force directed away from thechest wall as the inflatable jacket is inflated. That is, thecompression paddle of the present technology along with a non-rigidjacket (to form a compression paddle assembly) helps to prevent breasttissue at or near the chest wall to be positioned or slip away and/orout of the bottom wall and, thus, be out of the field of view duringimaging. The second portion helps to push or create a surface that has avector of surface away from the chest wall to maintain breast tissue inthe field of view during imaging. This configuration also helps toensure not only to have breast tissue in the field of view, but also tomaintain more uniform compression of the breast without having pressureor pinch points to a patient which may cause patient discomfort. In anembodiment, the first portion is generally straight and the secondportion is generally straight. Alternatively, the first portion caninclude a first section and a second section in which the first sectionis generally non-coplanar to the second section and, optionally, thefirst section is generally straight and the second section is generallystraight. The front wall 102 is understood to be the height of thecompression paddle 100. In an embodiment, the first portion 106 and thesecond portion 108 have different heights relative to the top of thefront wall. As a nonlimiting example, a height (H1) of the first portion106 is less than a tallest height (H2) of the second portion 108.Additionally or alternatively, a height (H1) of the first portion 106can be generally constant (i.e., horizontal) and a height (H2) of thesecond portion 108 can vary, e.g., linearly or non-linearly. In anembodiment, the front wall 102 is vertical. In another embodiment, thefront wall 102 is slightly off-angle from vertical, such as when thecompression paddle is applied to the breast. Where a front wall of acompression paddle is off-angle from vertical, such a front wallfacilitates in extending further into the chest wall in comparison to aknown flat compression paddle.

To compress a breast, a compression paddle assembly of the presenttechnology, having a compression paddle and a non-rigid jacket, isapplied to the breast for a first compression. The compression paddleassembly is applied to the breast in a craniocaudal direction.Additionally or alternatively, the compression paddle assembly can movesolely in a craniocaudal direction, by tilting the compression paddleassembly, by laterally moving the compression paddle assembly, orcombinations thereof. Where the compression paddle assembly is laterallymovable, the assembly is movable under manual control or when motorized,optionally, under software control. The assembly can shift automaticallydepending on the view of the breast to be acquired. As the height of thefirst portion is less than a height of the second portion, under thefirst compression, the second portion can be in contact with breasttissue while there can be a clearance between the breast tissue and thefirst portion. A technologist or technician can further position atleast a portion of the breast tissue during the first compression. Inone embodiment, the non-rigid jacket can become resilient, e.g., byinflating an inflatable jacket, to place the breast under compressionvia a second compression. In another embodiment, the non-rigid jacketcan be a gel pad which becomes resilient when placed in compressionagainst breast tissue.

Referring now to FIGS. 11A-11E, another compression paddle 110 of thepresent technology is shown in which a bottom wall 114 has a firstportion 116 and a second portion 118. The first portion 116 is generallynon-coplanar to the second portion 118 in this configuration and thesecond portion 118 has a generally smooth curvature. In an embodiment,the second portion 118 is generally concave. Relative to the top of thefront wall, the first portion 116 has a height (H3) less than a tallestheight (H4) of at least a portion of the second portion 118. In thisconfiguration, the radius of the second portion 118 is about 1.5 inchesto about 3.5 inches, preferably about 2.5 inches. The enlarged radius ofthe second portion 118, e.g., larger than usual, is intended to improvechest wall comfort by, for example, having a generally smooth patientcontacting contour. According to an embodiment, the height (H3) of thefirst portion is generally constant, whereas the height (H4) of thesecond portion varies. Additionally or alternatively, the shape of thesecond portion 118 can be generally a smooth curve or other curvilinearshape. A front wall 112 can be vertical or slightly off-angle fromvertical when the compression paddle is applied to a breast.

FIGS. 12A-12E illustrate an embodiment of a compression paddle 120 ofthe present technology. The compression paddle 120 has a front wall 122and a bottom wall 124. The front wall can be generally vertical orslightly off-angle to vertical when the compression 120 is applied to abreast. The bottom wall 124 includes a first portion 124 and a secondportion 128 in which the second portion is an intermediate portionbetween the front wall and the first portion. The first portion isgenerally horizontal having a generally constant height (H5) relative tothe top of the front wall of the compression paddle 120. A tallestheight (H6) of the intermediate portion is no greater than the height(H5) of the first portion. In an embodiment, the height (H6) of theintermediate portion varies, e.g., in a linear fashion, has a generallysmooth curvature, or is generally curvilinear. In such a configuration,the shape of the intermediate portion relieves pulling of tissue at thechest wall of a patient. The compression paddle 120 can be used tocompress a breast as part of a compression paddle assembly with anon-rigid paddle jacket, preferably a gel pad paddle jacket. Thus, inalternative embodiment, where a gel pad paddle jacket is utilized withthe compression paddle 120, there are not two compression steps. Thecompression paddle assembly would be applied to the breast in onedownward motion. Additionally or alternatively, the technologist ortechnician could but preferably would not be manipulating the breasttissue upon compression.

Referring now to FIGS. 13A-13B, a method of compressing a breast using acompression paddle assembly of the present technology is shown. Forpurposes of illustration, the compression paddle 110 of FIGS. 11A-11E isshown, though any other compression paddle described herein can be used.The method includes at least positioning a breast on a breast platform,positioning the compression paddle assembly relative to the breast,immobilizing the breast by lowering the compression paddle assembly orcompressing the breast with the compression paddle assembly, and,optionally, inflating the paddle jacket 130 where an inflatable paddlejacket is utilized. Where applicable, lowering the compression paddleassembly or compression the breast initially with the compression paddleassembly applies a first amount of force on the breast. Inflating apaddle jacket applies an additional amount of force on top of the firstamount to aid in compressing the breast evenly for x-ray imaging, e.g.,by evenly distributing the force over the top surface of the breast.

Shown as an example in FIGS. 13A-13B, though any of the compressionpaddles described herein can be used, the breast platform extendslaterally up to the front wall of the compression paddle, such as up tothe bottom part of the front wall. In an alternative embodiment, thebreast platform extends laterally up to where the front wall contactsthe chest wall of a patient, in configurations in which the front wallof the compression paddle is tilted or off-angle. The breast platformdoes not just extend only up to where the first portion ends or is nolonger generally horizontal and parallel to the breast platform. Thisconfiguration helps to minimize how much of the breast tissue is out ofthe field of view. Where portions of breast tissue are not in the fieldof view and/or are pinched (e.g., due to thick and/or dense breast bythe chest wall) by the front wall, second portion, and/or portionbetween the front wall and second portion of the compression paddle,image processing techniques can be utilized to account for suchpotential distortions. Optionally, image processing techniques can beutilized in any event as tissue by the chest wall can often be denseand/or thick. With known flat compression paddles, such compressionpaddles need to compress breast tissue significantly from anterior toposterior to try to get as much breast tissue into the field of view asmuch as possible. Compression paddles of the present technology areconfigured such that not as much compression force can be needed toimage breast tissue, thus, potentially leading to a more comfortablemammogram. Preferably, the compression paddles of the present technologyapply about 25% to about 50% less compression force than that of a knownflat compression paddle, as measured from the output signal of a loadcell located behind where the compression paddle mounts to the imagingsystem (i.e., the paddle mount).

Referring now to FIGS. 14A-14C, shown is another embodiment of acompression paddle 140 of the present technology. In particular, FIGS.14A-14C illustrate modifications to the compression paddle of FIGS.12A-12E, though such modifications can be made to any of the compressionpaddles described herein. Shown in FIGS. 14A-14C are generally roundedcorners about the front wall to the bottom of the compression paddle andgenerally rounded corners about the front wall to the side wall.Compression paddle 140 includes modifications to facilitate greaterflexibility and greater conformity to breast tissue. Side walls 142 havea height lower about a portion between the front wall 144 and rear wall146 than that of the height of the front wall 144 and/or rear 146, e.g.,lower by about 20% to about 80%, preferably about 25% to about 50%.Having a side wall with a lower portion facilitates for articulation ofthe compression paddle 140 at the front wall 144. The compression paddle140 may also, optionally, include slots formed near the rear corners tofacilitate more flexure of the bottom of the compression paddle, as wellas the compression paddle 140 overall. Additional optional modificationsto increase the flexibility of the compression paddle 140 includevarying the thickness of the paddle (e.g., with a portion of the bottomof the compression paddle being thicker than other portions, such as themiddle portion having a thickness greater than the portions closer tothe side walls) and manufacturing the compression paddle 140 from moreflexible materials from known compression paddles (e.g., preferably madewith materials that are about 40% more flexible). In the example inwhich the middle portion of the bottom surface is thicker than theportions closer to the side walls, the thicker, middle portion helps tokeep the compression paddle 140 from wrapping around the front of thebreast, which can lead to problems with pain at the nipple, pushing thebreast toward the chest wall, and pushing the breast potentially off ofthe detector; having the portion of the bottom surface closer to theside walls be thinner than the middle portion may facilitate moresupport in the MLO position and may help the compression paddle 140conform better to a breast shape. Such a configuration may allow bettercompression in the axilla area and the inframammary fold. Thecompression paddle 140 can be used to compress a patient's breast withor without an inflatable jacket and/or a gel pad.

Shown in FIGS. 15A-15C are additional features to a compression paddle160 of the present technology. The bottom wall of compression paddle 160includes a generally concave surface 162, which generally may correspondin shape to a breast and/or a compressed breast. The generally concavesurface 162 can extend generally between the side walls 164 of thecompression paddle 162. Alternatively, a portion of the bottom surfaceincludes a generally concave surface 162, which helps to match thecontour of breast tissue. The generally concave surface 162 helps todistribute more equally forces applied to the breast to more closelycorrespond to the shape of the breast. Such a configuration may helpprovide more comfort to a patient as the breast is being compressed. Thegenerally concave surface 162 includes two outer edge portions 166 thatdefine a reference plane P, as well as a central portion 168. Thecentral portion 168 is non-coplanar with the outer edge portions 166,such that the central portion 168 is raised relative to or disposedabove the reference plane P. The central portion 168 may be level (e.g.,parallel to the reference plane P or an axis A of the paddle 160) or maybe pitched downward from a front wall 170 to a rear wall 172 of thepaddle 160. This may help further conform the paddle 160 to the shape ofthe breast.

The generally concave surface 162 may also help to prevent the breastfrom slipping and moving during image acquisition. As an example, thisconfiguration may help prevent slipping of the breast in the MLOposition by supporting the breast more, in comparison to known flatcompression paddles that often allow the breast to slip during imageacquisition. The generally concave surface 162 may have smooth curvatureor can have any other shape that is generally concave, e.g., the surface162 may include ridges, lines, and/or other elements from injectionmolding the compression paddle 160, the surface may have a generallytrapezoidal shape, etc. Additionally or alternatively, the compressionpaddle 160 can be used to compress a patient's breast with or without aninflatable jacket and/or a gel pad. In another embodiment, the generallyconcave surface 162 may not be uniformly concave from the front wall 170(i.e., the chest facing wall) to the rear wall 172. As compressed breasttissue may not extend as far back as the rear wall 172, the concavitymay be greater near the front wall 170 compared to the rear wall 172. Asan example, the bottom surface 167 may be generally concave near thefront wall 170 and may be flatter near the rear wall 172. In anadditional or alternative example, the radius of the generally concavesurface is greater near the front wall compared to the bottom surfacenear the rear wall. This non-uniformity may help to provide more evencompression from the nipple to the chest wall of the breast.

Generally, the compression paddles of the present technology describedherein may be more comfortable to a patient undergoing breastcompression during a mammogram or x-ray imaging of the breast. Thecompression paddles of the present technology described herein generallyrequire less compression force to be applied to accomplish the sametautness as that of a known flat compression paddle.

The paddles may be manufactured of substantially rigid or flexiblematerials. Use of rigid materials allows the paddle to sufficientlycompress the breast without deforming. For example, in the embodimentdepicted in FIGS. 15A-15C, a distance between the central portion 168and the referral plane may be substantially the same when the paddle 160is compressing a breast or not compressing a breast. For example, theconcave contour of the bottom wall may be substantially the same. Theparticular shapes and contours of disclosed herein may reduce oreliminate discomfort during breast compression.

In the embodiments in which a compression paddle utilizes an inflatablebag, a pressure sensor can be utilized to prevent overinflating orunderinflating the bag. In alternative embodiments, the volume of theinflatable bag can be calculated with use of syringe. Additionally oralternatively, a motorized setup can be used to inflate the bag,optionally, in which a mechanical component like a lead screw can beused to prevent from overinflating the bag.

It is to be appreciated that embodiments of the methods and apparatusesdiscussed herein are not limited in application to the details ofconstruction and the arrangement of components set forth in thefollowing description or illustrated in the accompanying drawings. Themethods and apparatuses are capable of implementation in otherembodiments and of being practiced or of being carried out in variousways. Examples of specific implementations are provided herein forillustrative purposes only and are not intended to be limiting. Inparticular, acts, elements and features discussed in connection with anyone or more embodiments are not intended to be excluded from a similarrole in any other embodiment.

Also, the phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. Any references toembodiments or elements or acts of the systems and methods hereinreferred to in the singular may also embrace embodiments including aplurality of these elements, and any references in plural to anyembodiment or element or act herein may also embrace embodimentsincluding only a single element. The use herein of “including,”“comprising,” “having,” “containing,” “involving,” and variationsthereof is meant to encompass the items listed thereafter andequivalents thereof as well as additional items. References to “or” maybe construed as inclusive so that any terms described using “or” mayindicate any of a single, more than one, and all of the described terms.

All parts, ratios, and percentages herein, in the Detailed Descriptionand Claims are by weight and all numerical limits are used with thenormal degree of accuracy afforded by the art, unless otherwisespecified.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm”.

It should be understood that every maximum numerical limitation giventhroughout this specification includes every lower numerical limitation,as if such lower numerical limitations were expressly written herein.Every minimum numerical limitation given throughout this specificationincludes every higher numerical limitation, as if such higher numericallimitations were expressly written herein. Every numerical range giventhroughout this specification includes every narrower numerical rangethat falls within such broader numerical range, as if such narrowernumerical ranges were all expressly written herein.

All documents cited herein are, in the relevant part, incorporatedherein by reference; the citation of any document is not to be construedas an admission that it is prior art with respect to the presenttechnology. To the extent that any meaning or definition of a term or inthis written document conflicts with any meaning or definition in adocument incorporated by reference, the meaning or definition assignedto the term in this written document shall govern.

Having described above several aspects of at least one embodiment, it isto be appreciated various alterations, modifications, and improvementswill readily occur to those skilled in the art. Such alterations,modifications, and improvements are intended to be part of thisdisclosure and are intended to be within the scope of the technology.Accordingly, the foregoing description and drawings are by way ofexample only.

1. An x-ray breast imaging system comprising: an x-ray source; an x-raydetector; a breast support platform disposed between the x-ray sourceand the x-ray detector; a compression paddle disposed between the x-raysource and the breast support platform, the compression paddlecomprising: a front wall configured to be adjacent and face a chest wallof a patient during imaging; a bottom wall configured to extend awayfrom the patient's chest wall and to be adjacent a length of a top of acompressed breast, wherein the bottom wall comprises a central portionand two outer edge portions, wherein the central portion is disposed atan angle to the breast support platform, and wherein the compressionpaddle is movable; and a first axis substantially orthogonal to thefront wall.
 2. The x-ray breast imaging system of claim 1, wherein thetwo outer edge portions define a reference plane, and wherein thecentral portion is disposed above the reference plane so as to define aconcave surface extending from a first outer edge portion to the centralportion to a second outer edge portion.
 3. The x-ray breast imagingsystem of claim 2, wherein and the reference plane is substantiallyparallel to the breast support.
 4. The x-ray breast imaging system ofclaim 1, wherein the central portion of the bottom wall is pitched alongthe first axis from a high point proximate the front wall.
 5. The x-raybreast imaging system of claim 1, wherein the compression paddle isadapted to be disposed in: a compressing position wherein the compressedbreast is disposed between the compression paddle and the breastplatform; and a non-compressing position wherein the compressed breastis not disposed between the compression paddle and the breast platform,and wherein the bottom wall comprises a substantially similar contour inboth the compressing position and non-compressing position.
 6. The x-raybreast imaging system of claim 4, wherein a distance between the centralportion and the reference plane is substantially identical in both thecompressing position and the non-compressing position.
 7. The x-raybreast imaging system of claim 1, wherein movement of the compressionpaddle is selected from a group consisting of movable only along acraniocaudal axis, movable only laterally, and combinations thereof 8.The x-ray breast imaging system of claim 1, wherein the x-ray source isconfigured to selectively emit an imaging x-ray beam, and wherein thex-ray source is configured to move along an arc.
 9. The x-ray imagingsystem of claim 8, wherein the x-ray breast imaging system is a breasttomosynthesis x-ray breast imaging system.
 10. A compression paddle foran x-ray breast imaging system comprising: a front wall configured to beadjacent and face a chest wall of a patient during imaging; and a bottomwall configured to be adjacent a length of a top of a compressed breast,the bottom wall extending away from the patient's chest wall andcomprising two outer edge portions and a central portion non-coplanarwith the two outer edge portions, wherein the central portion isdisposed at an angle to the two outer edge portions.
 11. The compressionpaddle of claim 10, further comprising a non-rigid material spanning thetwo outer edge portions.
 12. The compression paddle of claim 10, furthercomprising an intermediate portion disposed between the front wall andthe central portion and comprising a radius having a generally smoothcurvature. 13.-14. (canceled)
 15. The compression paddle of claim 12,wherein the bottom wall has a concave portion and a convex portionrelative to the compressed breast.
 16. The compression paddle of claim15, wherein the convex portion is where the bottom wall meets theintermediate portion.
 17. (canceled)
 18. The compression paddle any ofclaim 10, wherein the front wall is slightly off-angle from vertical.19.-33. (canceled)
 34. The compression paddle of claim 10, furthercomprising a side wall disposed proximate each of the two outer edgeportions.
 35. The compression paddle of claim 34, wherein the outer edgeportions define a reference plane and wherein the sidewalls comprise asidewall height above the reference plane.
 36. The compression paddle ofclaim 35, wherein the front wall comprises a front wall height above thereference plane, wherein the front wall height is greater than thesidewall height.
 37. The compression paddle of claim 10, furthercomprising a bracket for releasably securing the compression paddle tothe imaging system.
 38. The compression paddle of claim 35, wherein thereference plane is substantially parallel to an axis of the compressionpaddle.